Portable, folding tray retainer and stand (multipurpose)

ABSTRACT

A portable litter tray holder and stand including a central discoid member, a mounting arm having a horizontal portion rigidly attached to the central member and a vertical-stand portion attached in upright relation to one side of the litter; and a pair of extension arms each having a horizontal portion pivotally attached to the central member and extending over the litter to terminate in a vertical-stand portion attached in upright relation to the opposite side of the litter.

United States Patent 1 Bartholomew et al.

[4 1 Mar. 5, 1974 PORTABLE, FOLDING TRAY RETAINER AND STAND(MULTIPURPOSE) [75] inventors: Hans B. Bartholomew; Maureen A.

Hunt, both of San Antonio, Tex.

[73] Assignee: The United States of America as represented by theSecretary of the Air Force, Washington, DC.

22 Filed: May 23, 1972 21 Appl. No.: 256,067

[52] US. Cl. 5/332, 108/49 [51] Int. Cl A47b 23/00 [58] Field of Search5/332; 248/167, 108/49 [56] References Cited UNITED STATES PATENTS1,308,034 7/1919 Bonnifield 108/49 2,644,660 7/1953 Dudley 5/3323,340,826 9/l967 .lenssen [08/49 l,93l,584 l0/l933 Luff 248/1671,338,486 4/1920 Burdick. 248/167 X 1,979,843 1l/l934 Roos i 248/167 XPrimary ExaminerPaul R. Gilliam [5 7 ABSTRACT A portable litter trayholder and stand including a central discoid member, a mounting armhaving a horizontal portion rigidly attached to the central member and avertical-stand portion attached in upright relation to one side of thelitter; and a pair of extension arms each having a horizontal portionpivotally attached to the central member and extending over the litterto terminate in a vertical-stand portion attached in upright relation tothe opposite side of the litter.

9 Claims, 5 Drawing Figures BACKGROUND OF THE INVENTION This inventionrelates generally to the field of service tray supports and, inparticular, to an improved combined portable tray support and standespecially adaptable for use with a litter-borne patient.

In the medical evacuation of litter or stretcher-borne patients by air,heretofore, foods, medicines, dressings, instruments and the like havebeen generally dispensed from and/or supported on service trays eitherplaced on the patients chest or abdomen, on the cabin floor next to thelitter, or, in some instances, held by an air crew member. It is readilyapparent that such methods are manifestly unsatisfactory for use withlitter-borne patients both from the standpoints of inconvenience andcomfort, and from the potentially unsafe conditions resulting therefrom.Thus, it is obvious that a clear and present need exists for some meansof providing improved support for such service trays in the closeproximity to the litter patient that would be required for convenience,comfort and safety.

Previously-used or proposed tray supporting means have generallyincluded either the upright stand frequently found in hospital rooms andwhich is manually movable to a position adjacent to the patient, or,alternatively, table-like members pivoted to the hospital or patient beditself have been employed. The relative size, weight and obviousbulkiness of the former, and the need for the substantial support of thehospital bed structure of the latter clearly makes either methodimpractical for utilization with a litter-borne patient, particularlywhen being transported by air. Therefore, it is self-evident that animproved portable-type of tray support is required, such as the traysupport and stand structure of the present invention, to be hereinafterdescribed in the following summary and detailed description, whichcombines positive means for retaining the tray being supported thereby,with an integral stand portion that is releasably supported on oppositesides of the litter.

SUMMARY OF THE INVENTION The present invention consists briefly in aportable tray holder and stand that includes a central, discoid member;a main mounting arm having a horizontal portion fixedly interconnectedwith the central member and a vertical portion having contoured clipmeans for engagement with the pole on one side of a litter; and a pairof extension arms each having a horizontal portion interconnected withthe central member and adapted to extend over the litter, and a verticalportion having contoured clip means for engagement with the other poleof the litter. The central member is uniquely jointed in configurationto thereby specifically provide for the pivotal attachment thereto andthus the adjustment of the extension arms between an extended positiondisposed over the litter and a stow-away or folded position adjacent tothe mounting arm. The top surface of the central member, and thehorizontal portions of the mounting and extension arms provide supportfor a service tray. Resilient restraint means, to be describedhereinafter in more detail, are incorporated on the upper surface ofeach of the mounting and extension arms to provide a positive hold onthe tray.

Inherent objects and advantages of the present invention will appearhereinafter in the following disclosure, taken in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 4 is another perspective view,somewhat similar to that of FIG. 3, but showing a patient resting in thelitter and with a food tray being supported by the inventive tray holderand stand; and

FIG. 5 is an exploded view, in perspective, depicting further details ofthe inventive litter tray holder and stand. A

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring generally to thedrawings and, in particular, to FIGS. 1 and 2 thereof, the new andimproved combined litter tray holder and stand of the present inventionis indicated generally at 10 as including principally a main, singlemounting arm member 12, that is supportable on one side of a litter,seen at 15 in FIG. 2; a pair of identical extension arm members 13 and14 that may be mounted to the opposite side of the litter 15; and acentrally and/or intennediately-disposed, discoid member 11 thatinterconnects the mounting arm member 12 with the extension arm members13 and 14 in a unique and yet simplified manner to be described indetail hereinafter with specific reference to FIG. 5.

The aforementioned interconnection between said mounting arm member 12,and extension arm members 13 and 14 is provided by the said central,discoid member 11 being made jointed in configuration through itsinclusion of a lower, discoidal-shaped housing joint portion, indicatedgenerally at 22 and which has connected flat upper and lower surfaces,at 23 and 24 respectively, between which is combined-in unique relationto each other, first, a horizontally-oriented peripheral orcircumferential and circular opening 26 into which is rigidly attachedthe end of a horizontallydisposed arm portion 12a of the mounting armmember 12, and, secondly, a pair of horizontally-oriented, identical andoppositely-positioned peripheral or circumferential and arcuate'shapedslots, one of which is indicated at 25, into which may be attached forpivotal movement the respective ends of a horizontally disposed armportion 13a and 14a of each of the extension arm members 13 and 14.

The previously-described rigid attachment'between thehorizontally-disposed arm portion 12a of the mounting arm member 12 andthe housing portionopening 26 is actually effected by the engagement ofa combined housing pin and pivot at 27 that is interconnected within,and between the said'opening'26, and aligned openings formed in, oradjacent to, the end of arm portion 12a and within the housingportion-upper surface 23. The pivotal attachment of each extension armmember-horizontally-disposed arm portion 13a and 14a within thecircumferential housing portionslots, as at 25, may be respectivelyaccomplished by means of similar, combined housing pins and pivots, at28 and 29, which likewise engage within aligned openings disposed in, oradjacent to the end of each arm portion 13a, 14a and within theappropriate location in the said housing portion-upper surface 23. Withthis unique and yet simplified use of the jointed housing portion 22and, in particular, with the horizontallydisposed arm portions 13a and14a being pivotally attached to, and disposed within theoppositely-disposed arcuate and circumferential slots, as at 25, thequick and easy adjustment of the extension arm members 13 and 14 withinthe said arcuate-shaped slots, as at 25, and between the extendedposition of FIG. 2 and the stow away or folded position of FIG. 1 isthereby facilitated and promoted.

The above-noted mounting arm member 12 further incorporates an integral,vertically-disposed arm portion 12b to the lower end of which may beincorporated a resilient litter or mounting and clamping clip 16 that,in accordance with the unique teachings of the present invention, hasbeen especially contoured and therefore made particularly adapted forthe mounting of the said vertically-disposed arm portion 12b inreleasable, upright relation on the pole formed on one side of thelitter, at 15, as is illustrated in FIG. 2, for example, which figureconstitutes a depiction of the first step or step No. l in theassembling of the inventive tray holder and stand to a selected litter.In this regard, FIG. 1 represents a showing of the stow away or foldedposition of the invention, as noted hereinbefore, in which the extensionarm members 13 and 14 have been pivoted to their collapsed positionsadjacent to, and on opposite sides of the mounting arm member 12. Thus,itis obvious that one key feature of the tray holder and stand of thepresent invention resides in its inherent capability of being quicklyremoved from the litter 15, when not in use, and thereafter theextension arm members 13 and 14 being easily adjusted to their foldedposition of FIG. 2, through means of the specially jointed discoidmember 11, as described hereinb'efore. Until its further use isrequired, the folded and obviously compact condition of the inventivetray support and stand 10 may be located in a relatively out-of-the-wayposition in the aircraft.

When it is desired to utilize the inventive tray holder and stand 10,the latter may be very easily brought to the litter location, theextension arm members 13 and 14 manually pivoted in the arcuate slots,as at 25, to the extended position of FIG. 2, and thereafter thevertically-disposed arm portion 12b of the mounting arm member 12 may beinitially supported in upright relation to one pole of the litter 15, bythe releasable engagement therewith of its resilient and contouredlitter or mounting and clamping clip 16. Then, the extension arm members13 and 14 which, at this time (FIG. 2), have already been adjustedoutwardly to their extended position, may now be mounted to the oppositepole of the litter 15, through the releasable engagement therewith ofthe litter or mounting and clamping clips, indicated at 17 and 18 asbeingrespectively formed on and adjacent to the lower end of each of avertically-disposed arm portion 13b and 14b formed on said extension armmembers 13 and 14. This constitutes the final step or step No. 2involved in mounting the invention to, and in supporting uprightrelation on, a litter, as at 15. As in the case of the clip 16, clips 17and 18 have been specifically contoured to exactly conform with, andthus precisely accommodate the particular size of the appropriate poleof the litter 15 in a relatively and sufficiently tight-fitting relationthereto to thus provide an appropriate support for a selected servicetray, such as the food tray, indicated at 19 in FIG. 4 as being therebydisposed in close proximity to a patient 20 shown resting on a pillow21.

To retain the above-described housing pins and pivots 27, 28 and 29 intheir respective interconnecting openings provided in thehorizontally-disposed ends of the arms 12, 13 and 14 and within thehousing portion 22, the central member 11 also incorporates a unique,upper tension plate portion, indicated generally at 30. Tension plateportion 30 is resiliently attached to, and generally maintained on topof, said lower housing portion 22, with its inner surface therefore inresilient, contacting and supporting relation on the top or upper endsof the aforementioned housing pins and pivots 27, 28 and 29, through theuse of a tension spring 31 that is retained in contacting relation withthe underside of the tension plate portion 30 and is further positionedwithin an appropriately-sized, recessed opening 32, formed in the lowerhousing portion-upper surface 23, by means of a housing screw at 33.Additional pivot pins, at 34, are utilized to complete and provide forthe adequate resilient mount of the tension plate portion 30 to thehousing portion 22.

With the foregoing use of the novel tension plate portion 30 and, inparticular, by the selective adjustment of the housing screw 33, thedegree of tension being applied by the said tension plate portion 30 tothe housing pins and pivots 27, 28, 29 and 34, as well-as that beingimpressed thereby upon the horizontally-disposed arm portions 13a and14a, may be uniquely and easily controlled and adjusted to that requiredfor providing a desired degree of restraint to the said extension armmembers 13 and 14, both while located in either stow away or supportingpositions and particularly during their pivotal movement therebetween.In this connection, further restraint is provided by the use ofperipheral slots or notches, as depicted at 36, 37 and 38 as beingincorporated in a depending skirt portion 35 formed on the circumferenceof the tension plate portion 30, as is clearly illustrated in FIG. 5.Depending skirt portion 35 is designed to overlap the periphery of theupper housing portion 23, when the tension plate portion 30 is assembledthereto, and thereby resiliently contact the upper surfaces of each ofthe extension arm member-horizontally-disposed arm portions 13a and 14a,under the action of the tension spring 31. With the use of the notchedand depending skirt portion 35, when the extension arm members 13 and 14are pivoted to their stow-away or folded position of FIG. 1, forexample, their horizontally-disposed arm portions 13a and 14arespectively snapped upwardly into, and positively engage within thepair of closely spaced notches at 37 and 38 which are located nearlyadjacent to the horizontal end of the mounting arm member 12. In thismanner, the notches 37 and 38 act both as a positive restraint to theextension arm members 13 and 14, when in their folded position, and as apositive guide means for quickly and easily directing and automaticallyproviding a definite indication as to exactly when the appropriate stowaway position has been reached.

When it is desired to pivot the folded extension arm members 13 and 14outwardly to their properly extended position of FIG. 2, for example, asimilar set of slots or notches, as at 36, which are incorporated alongthe circumference of the skirt portion 35 at the same relative andoppositely-disposed position, become operative to engage with andprovide a positive restraint to the horizontally-disposed-extension armportions 130 and 14a. Again, the notches, as at 36, are so located as toprovide for both the previously referred to positive restraint on, andto further act as a quick means of precisely indicating the correctextended positions of the extension arm members 13 and 14, at whichtime, the vertically-disposed arm portions 13b and 14b thereof have beenaccurately positioned for the resilient attachment of the mounting clips17 and 18 thereof with the appropriate pole of the litter 15.

The combined tray holder and stand also uniquely incorporates means forpositively and releasably retaining a selected service tray, as at 19 inFIG. 4, on top of the previously-described central discoid member 11 insimultaneous supporting contact on the upper surfaces of thehorizontally-disposed arm portions 12a, 13a and 14a. For this expresspurpose, the said tray-retaining means includes a resilient retainerclip, indicated generally at 39 as being positioned on top of thehorizontally-disposed arm portion 12a of the mounting arm 12, and a pairof identical resilient tray clips, indicated generally at 40 and 41 asbeing respectively affixed on top of the said horizontally-disposed armportions 13a and 14a of the extension arm members 13 and 14. Each ofsaid tray clips 40, 41 incorporates a base supporting clip-portion, at42 and 43 respectively, that are directly supported to the arm portions13a and 14a, and a resilient, direct tray-engaging clip-portion, at 44and 45, re spectively. With this simplified and yet novel tray retainingstructure, after mounting the combined tray holder and stand 10 to thelitter 15, as explained hereinbefore, the positive emplacement andretention of a food tray, for example, as at 19 in FIG. 4, in supportingrelation on top of the discoid central member 11 and the horizontalportions of the mounting and extension arm members 12, 13 and 14 may bequickly accomplished simply by resting the tray 19 on the surfacesmentioned above with one side edge thereof being centered on, andresting or resiliently engaged against and within the retainer clip 39,and, thereafter, snapping the oppositely-disposed corners disposed onthe opposite side edge of the tray 19 downwardly until they have beenresiliently engaged within the resilient, direct, tray-engagingclip-portions 44 and 45 respectively forming part of the tray clips 40and 41. Of course, at this point, the bottom surface of each of theabovereferred to corners of the tray 19 will be resting in supportingrelation on the base supporting clip-portions, indicated respectively at42 and 43 in FIG. 5.

The above-noted retainer clip 39 may be further uniquely and adjustablymounted for movement to various positions relative to thehorizontally-disposed arm portion 120 of the mounting arm member 12 tothereby provide for the easier removal of the tray 19 and to accommodatetrays of different sizes. To this end, the re tainer clip 39incorporates an integral pair of spacedapart, elongated and parallelretainer clipsupporting arm members, indicated at 46 and 47. The latterare slidably engaged within relatively elongated cylindrical-supportingportions 48 and 49 that are affixed, as clearly depicted in FIG. 5, onopposite sides of the horizontally-disposed arm portion 12a. Topositively retain said elongated retainer clip-supporting arm members 46and 47 in a selectively adjustable position relative to, and within,said cylindrical portions 48 and 49 and thereby provide for theaforementioned variable adjustment of the retainer clip 39, a retainerspring, such as that indicated at 50, is positioned within each of thecylindrical portions 48 and 49 in surrounding and resiliently-contactingand substantially gripping relation to each of the retainerclip-supporting arm members 46 and 47 that are extending therewithin. Ascrew and washer element, as at 51 and 52, and at 53 and 54,respectively, may be utilized to retain said retainer springs, as at 50,within the particular cylindrical portion, as at 48 and 49. Thus, whenit is desired to readjust the spacing between the tray clips 40 and 41,and the retainer clip 39, the latter may be rather easily slidablyadjusted to the desired position to thereby accommodate the particulartray to be supported thereto.

Thus, a new and improved portable and combined tray holder and standdevice has been developed by the present invention and which is bothreadily installed on a litter, and further both incorporates a centerdiscoid joint facilitating folding of the device for storage, in uniquecombination with a positive, bracketed restraint means for the supportedtray. Moreover, although the inventive device includes speciallycontoured spring clamps for attachment to the opposite poles of alitter, it can be easily modified for use in other applications, such asbuses, cafes, drive-ins, ships and trailers, without departing from thetrue spirit or scope of the invention. Furthermore, the present trayholder and stand, which is usable for suspending service trays, such asthat used for food, instruments and medications, in a functionalposition, may be easily used in a similar manner to elevate a patientsarm in a stable position and/or to serve as a convenient and safe workarea for supporting certain equipment required to perform asepticmedical procedures, as for example, catheterization or tracheostomysuctioning.

We claim:

1. A portable, collapsible and compact service tray holder and standdevice for mounting a food and/or medicine tray or the like on and overa litter and/or other supporting structure in close proximity to apatient, or other occupant or user, and comprising; a central, discoidand tray-supporting member; a main, mounting arm member having ahorizontal arm portion providing further support for the tray and beingfixedly attached to said central member, and a vertical arm portionintegrally formed to said horizontal arm portion and equipped withfirst, releasable means on the lower end thereof for supporting andattaching one side of said central member in vertically-upright relationto a side or portion of, and over the litter, or other supportingstructure; and a pair of extension arm members each having a horizontalarm portion providing still further support for the tray when in asecond, extended position of adjustment relative to each other and beingpivotally attached to said central member for adjustment between both afirst, inward, folded, closed and collapsed position in stored relationagainst, adjacent and parallel to opposite sides of said mounting armmember, and the said second, extended tray-supporting position insubstantially oppositely-disposed relation to said mounting arm member;each of said extension arm members incorporating a vertical arm portionintegrally formed with the horizontal arm portions thereof and Orientedin and extending over the litter, or other supporting structure to avertically-upright relation on the side of said central member remotefrom said mounting arm member, and with second, releasable meansincorporated on the lower end of each thereof and attached to theopposite side of said litter, or other supporting structure; saidcentral, discoid member consisting of jointed means for interconnectingsaid main mounting and extension arm members in respective rigid andadjustable relation thereto, and comprising; a first, lower housingjoint portion having a horizontal opening and at least onearcuate-shaped slot for respectively receiving therein in rigid, andadjustable and pivotal relation the horizontal arm portions of said mainmounting arm and extension arm members; and a second, uppertension-applying means positioned over and in indirect, and resilientcontact with the upper surface of said first, lower housing jointportion; said tensionapplying means having a peripheral portionextending downwardly in'overlapping relation relative to thecircumference of said lower housing joint portion, and incorporatingfirst and second, resilient stop means in periodic engagement with, andreleasabiy and respectively retaining the horizontal arm portions ofeach of said extension arm members in a relatively taut relation intheir substantially oppositely-disposed first, closed and second,extended positions of adjustment.

2. A portable, collapsible and compact service tray holder and standdevice as in claim 1, wherein said tension-applying means comprisesa'discoid-shaped upper tension plate member adjustably positioned to,and on top of said housing joint portion; and said first and second,resilient stop means each comprises an extension arm-receiving anddownward-facing notch formed in appropriately-spaced relation along adepending periphery of said tension plate member.

3. A portable, collapsible and compact service tray holder and standdevice as in claim 1, wherein said tension applying means comprises adiscoid-shaped upper tension plate member having resilient meansadjustably attached to said housing joint' portion.

4 A portable, collapsible and compact service tray holder and standdevice as in claim 3, wherein the resilient attachment means betweensaid upper plate member and lower housing portion comprises a tensionspring element intermediately disposed between the underside of saidtension plate member and a centrallydisposed recess formed in saidhousing portion; and a screw element attached through said tension platemember from the upper side thereof for engagement within and therebysimultaneously providing a guide means for said tension spring, andadjustment of the tension being impressed by said tension plate on saidextension arm members.

5. A portable, collapsible and compact service tray holder and standdevice as in claim 4, wherein said central, discoid member-jointed meansfurther comprises a relatively short pivot pin interconnected betweenand engaged in tight-fitting relation within a first opening formed inthe ends of, and thereby rotating in simultaneous relation with, thepivotal adjustment of the horizontal arm portions of each of saidextension arm members and a second opening incorporated in the uppersurface of said lower housing joint portion in alignment with each ofsaid first-named openings; said jointed means still further comprisingan attachment pin rigidly interconnecting the horizontal arm portion ofsaid mounting arm member in the said horizontal opening of said central,discoid member-housing joint portion; said attachment pin and said pivotpins extending further upwardly through the top surface of said lowerhousing joint portion in resiliently-disposed contact with the undersideof, and thereby providing a floatingtype support for, and with saidupper tension plate member through the inherent action thereagainst ofthe said tension spring element.

6. A portable, collapsible and compact service tray holder and standdevice as in claim 5, wherein the variable adjustment of said screwelement, relative to the tension spring element, is automaticallyresponsive to vary the tension being applied to said extension armmembers, through the said peripheral-resilient stop means of saidtension plate member, and said pivot pins in direct proportion to saidadjustment.

7. A portable, collapsible and compact service tray holder and standdevice as in claim 6, wherein the releasable means of said vertical armportions of each of the mounting and extension arm members each comprisea flexible clamping device.

8. A portable, collapsible and compact service tray holder and standdevice as in claim 7, wherein said flexible clamping device comprises aresilient tray clip contoured to precisely accommodate each pole of alitter.

9. A portable, collapsible and compact tray holder and stand device asin claim 8, wherein said horizontal- Iy-disposed arm portions of saidmounting, and extension arm members collectively incorporatetraybracketed restraint means in supporting relation thereto forpositively holding a selected tray thereon, said bracketed restraintmeans being adjustable to thereby accommodate trays of various sizes.

1. A portable, collapsible and compact service tray holder and standdevice for mounting a food and/or medicine tray or the like on and overa litter and/or other supporting structure in close proximity to apatient, or other occupant or user, and comprising; a central, discoidand tray-supporting member; a main, mounting arm member having ahorizontal arm portion providing further support for the tray and beingfixedly attached to said central member, and a vertical arm portionintegrally formed to said horizontal arm portion and equipped withfirst, releasable means on the lower end thereof for supporting andattaching one side of said central member in vertically-upright relationto a side or portion of, and over the litter, or other supportingstructure; and a pair of extension arm members each having a horizontalarm portion providing still further support for the tray when in asecond, extended position of adjustment relative to each other and beingpivotally attached to said central member for adjustment between both afirst, inward, folded, closed and collapsed position in stored relationagainst, adjacent and parallel to opposite sides of said mounting armmember, and the said second, extended tray-supporting position insubstantially oppositely-disposed relation to said mounting arm member;each of said extension arm members incorporating a vertical arm portionintegrally formed with the horizontal arm portions thereof and orientedin and extending over the litter, or other supporting structure to avertically-upright relation on the side of said central member remotefrom said mounting arm member, and with second, releasable meansincorporated on the lower end of each thereof and attached to theopposite side of said litter, or other supporting structure; saidcentral, discoid member consisting of jointed means for interconnectingsaid main mounting and extension arm members in respective rigid andadjustable relation thereto, and comprising; a first, lower housingjoint portion having a horizontal opening and at least onearcuate-shaped slot for respectively receiving therein in rigid, andadjustable and pivotal relation the horizontal arm portions of said mainmounting arm and extension arm members; and a second, uppertension-applying means positioned over and in indirect, and resilientcontact with the upper surface of said first, lower housing jointportion; said tension-applying means having a peripheral portionextending downwardly in overlapping relation relative to thecircumference of said lower housing joint portion, and incorporatingfirst and second, resilient stop means in periodic engagement with, andreleasably and respectively retaining the horizontal arm portions ofeach of said extension arm members in a relatively taut relation intheir substantially oppositely-disposed first, closed and second,extended positions of adjustment.
 2. A portable, collapsible and compactservice tray holder and stand device as in claim 1, wherein saidtension-applying means comprises a discoid-shaped upper tension platemember adjustably positioned to, and on top of said housing jointportion; and said first and second, resilient stop means each comprisesan extension arm-receiving and downward-facing notch formed inappropriately-spaced relation along a depending periphery of saidtension platE member.
 3. A portable, collapsible and compact servicetray holder and stand device as in claim 1, wherein said tensionapplying means comprises a discoid-shaped upper tension plate memberhaving resilient means adjustably attached to said housing jointportion.
 4. A portable, collapsible and compact service tray holder andstand device as in claim 3, wherein the resilient attachment meansbetween said upper plate member and lower housing portion comprises atension spring element intermediately disposed between the underside ofsaid tension plate member and a centrally-disposed recess formed in saidhousing portion; and a screw element attached through said tension platemember from the upper side thereof for engagement within and therebysimultaneously providing a guide means for said tension spring, andadjustment of the tension being impressed by said tension plate on saidextension arm members.
 5. A portable, collapsible and compact servicetray holder and stand device as in claim 4, wherein said central,discoid member-jointed means further comprises a relatively short pivotpin interconnected between and engaged in tight-fitting relation withina first opening formed in the ends of, and thereby rotating insimultaneous relation with, the pivotal adjustment of the horizontal armportions of each of said extension arm members and a second openingincorporated in the upper surface of said lower housing joint portion inalignment with each of said first-named openings; said jointed meansstill further comprising an attachment pin rigidly interconnecting thehorizontal arm portion of said mounting arm member in the saidhorizontal opening of said central, discoid member-housing jointportion; said attachment pin and said pivot pins extending furtherupwardly through the top surface of said lower housing joint portion inresiliently-disposed contact with the underside of, and therebyproviding a floating-type support for, and with said upper tension platemember through the inherent action thereagainst of the said tensionspring element.
 6. A portable, collapsible and compact service trayholder and stand device as in claim 5, wherein the variable adjustmentof said screw element, relative to the tension spring element, isautomatically responsive to vary the tension being applied to saidextension arm members, through the said peripheral-resilient stop meansof said tension plate member, and said pivot pins in direct proportionto said adjustment.
 7. A portable, collapsible and compact service trayholder and stand device as in claim 6, wherein the releasable means ofsaid vertical arm portions of each of the mounting and extension armmembers each comprise a flexible clamping device.
 8. A portable,collapsible and compact service tray holder and stand device as in claim7, wherein said flexible clamping device comprises a resilient tray clipcontoured to precisely accommodate each pole of a litter.
 9. A portable,collapsible and compact tray holder and stand device as in claim 8,wherein said horizontally-disposed arm portions of said mounting, andextension arm members collectively incorporate tray-bracketed restraintmeans in supporting relation thereto for positively holding a selectedtray thereon, said bracketed restraint means being adjustable to therebyaccommodate trays of various sizes.